Before vowels e, é, i, y or ý (including diphthongs and triphthongs that start with those letters), /s/ can be optionally transliterated as "c".

Also the phonemes /n/, /f/, /sh/ and /l/ have alternate transliterations, that belong to the Classical period of the language. After some time, the ortography of the language suffered a reformation and those classical forms transformed in the shortened forms (n, f, sh and l).